title: Synthesis of a set of highly clustered monosulfated galactopyranosides.
abstract: There are several biological events that are known to involve certain sulfated saccharides. In many such cases, however, clustered ligands have been shown to be more effective than monovalent saccharides. A set of 6-aminohexyl glycosides of 2,3,4 or 6-monosulfated galactose have been synthesized and linked to polyglutamic acid. Because of the bulky aglycon employed, the 2-OH group of the key compound, 6-benzyloxycarbonylaminohexyl 4,6-O-benzylidene-beta-D-galactopyranoside was markedly less reactive than 3-OH. Thus, site-specific acetylation of 3-OH was readily carried out to obtain 2-O-sulfated galactosides, and even the direct sulfation of 3-OH afforded the 3-sulfate in a reasonable yield. On the other hand, the key compound was unexpectedly resistant to 2,3-O-dibenzylation or 2,3-O-dibenzoylation, both of which were meant for regioselective cleavage of 4,6-benzylidene to obtain the 4-sulfate.
authors.affiliation: Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA. tomo@amugw.aichi-med-u.ac.jp
authors.forename: T
authors.initials: T
authors.lastname: Yoshida
mesh_terms: D000818:Animals; D002236:Carbohydrate Conformation; D005697:Galactosides / Q000138:chemical synthesis* / Q000737:chemistry; D007202:Indicators and Reagents; D019041:L-Selectin / Q000378:metabolism; D008024:Ligands; D051379:Mice; D019906:Nuclear Magnetic Resonance, Biomolecular; D011099:Polyglutamic Acid; D013329:Structure-Activity Relationship
chemical_list: C110940:6-benzyloxycarbonylaminohexyl-4,6-O-benzylidene-galactopyranoside; D005697:Galactosides; D007202:Indicators and Reagents; D008024:Ligands; D019041:L-Selectin; D011099:Polyglutamic Acid